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The Guanlong wucaii dinosaur is the oldest ancestor of T. rex. (Photo: Zhongda Zhang/IVPP) |
Researchers have announced the discovery of the ancestor of the fearsome T. rex. The oldest fossil of a tyrannosaur dates back 160 million years.
The research team was surprised to find that this 3-meter-long dinosaur had a colorful crest on its head. This discovery could provide insights into how short-legged, long-tailed dinosaurs evolved into T. rex over the course of 100 million years. The new species was found in the Junggar Basin, a region rich in dinosaur fossils in the remote northwest of China.
A local worker accidentally discovered two dinosaur skeletons, one of a 12-year-old adult and one of a 6-year-old juvenile. Both skeletons are relatively intact. The team named this late Jurassic dinosaur Guanlong wucaii, which translates from Chinese as “dragon with a crest.”
Professor James Clark, a paleontologist at George Washington University, stated: “Upon closer examination, we found that it is indeed a relative of T. rex. This makes it the most primitive known relative of the tyrannosaur family.”
The tyrannosaur group dominated as predators during the late Cretaceous period. This era, which occurred about 65-100 million years ago, marked the final chapter before this group went extinct. At that time, T. rex was ruling the land. The most famous member of the tyrannosaur lineage, which could grow to sizes of 9-13 meters, featured massive teeth and tiny forelimbs equipped with terrifying claws, becoming the star of many Hollywood films.
Professor Clark described G. wucaii: “The most striking feature is its crest on the top of its head. This is quite unusual for a carnivore. This crest must have been quite colorful and served as a display.”
The creature also shares some characteristics with T. rex, such as sharp teeth, short forelimbs, and the ability to run on two hind legs. However, G. wucaii is distinctly smaller, measuring only 3 meters in length. Additionally, its more primitive skull and pelvic features suggest that it is an intermediate species between tyrannosaurs and coelurosaurs—an older group of dinosaurs that are ancestors of modern birds. Researchers hope this discovery will reveal early stages in the evolution of tyrannosaurs.
“Guanlong illustrates how the small coelurosaurian ancestor of tyrannosaurs evolved into the massive T. rex nearly 100 million years later,” Clark said.